None of the above answers.
Here's what I have, from one of the online groups I used to follow. (I would credit the original author, but I tend to copy and save this stuff to my own FAQ documents and have long since lost the link to the original post):
Q. I have a rules question. What does the "R>3" mean in the stat 1/1 R>3?
A. So a regular infantry squad rolls 1 red and 1 white die. The white hits on 4+ modified by terrain, movement, op fire, etc. (it’s anywhere from 3-6). The red die always hits on 6. It is never modified.
A team or half squad (1/1 R>3) is “half as effective” as a full squad. So the white die only counts if the red die is over 3.
Remember that the red die only hits on 6, but a red roll of 4, or 5, or 6 is still needed for the white die to even count (regardless of if the white die shows a “hit”). Thus a red die that gets a 6, hits by itself AND also allows the white die to count (as long as the white die also hits).
That roughly translates to the half squad hitting half as much as a full squad with its full 1 white, 1 red.
Hope that helps.